From f3af088deabc1c3f90d22c43dcda9c5b8344bc86 Mon Sep 17 00:00:00 2001
From: "B. Watson" <urchlay@slackware.uk>
Date: Thu, 9 Apr 2026 06:19:28 -0400
Subject: Rewrite the guts of print_ping_time() yet again. 7593 bytes free.

---
 src/jifsec.s | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

(limited to 'src/jifsec.s')

diff --git a/src/jifsec.s b/src/jifsec.s
index 4f3d3c8..15ae972 100644
--- a/src/jifsec.s
+++ b/src/jifsec.s
@@ -15,10 +15,32 @@
  _hz = $f0 ; must agree with timers.h!
 
  .import _scr_act_printnum, _scr_putc_active
+ .import _read_rtclok, _a2uint
  .import mulax10
 
  ; extern void print_jif_sec(unsigned int jiffies);
- .export _print_jif_sec
+ .export _print_jif_sec, _calc_ping_time
+
+_calc_ping_time:
+ jsr _a2uint
+ sta acc16
+ stx acc16+1 ; acc16 = timestamp in ping response
+ jsr _read_rtclok ; A/X = low 15 bits of RTCLOK
+ cpx acc16+1 ; has RTCLOK rolled over?
+ bcs @clok_ok
+ pha
+ txa
+ ora #$80
+ tax
+ pla
+@clok_ok:
+ sec
+ sbc acc16
+ pha
+ txa
+ sbc acc16+1
+ tax
+ pla ; A/X now holds "now" minus timestamp
 
 _print_jif_sec:
  jsr divbyhz
-- 
cgit v1.2.3